Questions tagged [gyroscopes]
A spinning wheel or disc in which the axis of rotation is free to assume any orientation by itself. When rotating, the orientation of this axis is unaffected by tilting or rotation of the mounting, according to the conservation of angular momentum. These devices are used for measuring or maintaining orientation and angular velocity.
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How do we stabilise satellites so precisely?
Look at the Hubble Ultra Deep Field photo. The stars in it are on the order of 1 arcsecond across. To an order of magnitude, this is $10^{-6}$ radians in a $10\text m$ telescope which was held steady ...
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Why don't spinning tops fall over?
One topic which was covered in university, but which I never understood, is how a spinning top "magically" resists the force of gravity. The conservation of energy explanations make sense, but I don't ...
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Can a car steer on a frictionless surface?
Do the front tires of a car act like gyroscopes, such that a car could steer on a frictionless surface?
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Why does a spinning top get back upright when knocked?
I have observed that, a spinning top, when toppled by knocking it with finger, becomes almost upright again (with negligible precessional motion), instead of undergoing precession while being heavily ...
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Why are spacecraft made to "spin" after launch?
At some point after launch, usually just before or after separation from the last booster stage, spacecraft are often made to "spin" (about the axis of their trajectory)? See e.g this You Tube video. ...
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What determines the direction of precession of a gyroscope?
I understand how torque mathematically causes a change to the direction of angular momentum, thus precessing the gyroscope.
However, the direction, either clockwise or counterclockwise, of this ...
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How do you explain spinning tops to a nine year old?
Why don't spinning tops fall over? (The young scientist version)
My nine year old son asked me this very question when playing with his "Battle Strikers" set. Having studied Physics myself, I am very ...
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What makes a wrist-energized gyroscope rotate faster?
I'm considering a wrist-energized gyroscope, shown below (after my daughter let it fall and it broke open). That one was sold as Roller Ball, but variants are known as Powerball, DynaBee, Dynaball, ...
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Would a double gyroscope still have gyroscopic properties?
Imagine you have a gyroscope that has two spinning parts, one on top of the other. When you pull the string, the two halves spin in opposite directions. Would this cancel out the gyroscopic properties,...
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What's the deal with the gyroscope?
In this article ("The problem with physics", Tony Rothman, ABC science) the author says in the 5$^\textrm{th}$ paragraph:
For example, one needs only first-semester equations to describe reasonably ...
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Magnet gyroscopic force spin
I was wondering whether a magnet exerts any measurable gyroscopic effects. I understand that magnetism is caused by alignment of spins of electrons which have angular momentum. (I realise that that ...
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how can you keep a gyroscope turning?
I'm trying to understand how do gyroscopes and cmgs used for navigating keep on spinning even though there's friction. Any engine/pushing mechanism I can think of will restrict the gyro's rotor to a ...
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Gimbal Lock: why is it a problem?
I was watching the video Gimble Lock - Explained, by videodumper, about the gimbal lock problem. I understood that during rotations it could happen that one DOF disappear. Looking at the middle part ...
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Defy gravity torques with gyroscopes?
Context
On the following drawing, a platform is hung from the ceiling not exactly from its centre of gravity. Because of this it can't sustain an arbitrary orientation for long; I want to increase ...
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Without using rotational mechanics, why does a gyroscope precess the direction it does?
When a top is spun, it will precess in some direction, either clockwise or counterclockwise. It's possible to find out which way using $\boldsymbol{\tau} = d\mathbf{L}/dt$ and $\boldsymbol{\tau} = \...
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Why does the heaviest point on a spinning ball tend to become the topmost pole? [duplicate]
I have a mostly hollow, small clear plastic ball. Inside the ball is a weight stuck to the edge but the weight is smaller than the ball so the ball will always come to rest with the weight at the ...
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Feynman's disk paradox used as a gyroscope?
I have recently learned about Feynman's disk paradox, where angular momentum is stored in the properties of the electric field. One example would be a coil with current going through whose axis is ...
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With respect to what does a Gyroscope maintain its orientation?
Assume ideal conditions, no friction, no energy loss in any form.
Just an ideal gyro, in ideal conditions, spun into rotation and left alone. And placed somewhere on earth.
From what I've read so ...
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Does motorcycle counter-steering work by precessional motion?
When a motorcycle is going over a particular speed ($\approx 20$ m/h or 30 km/h) you learn in motorcycle class the best way to steer is using the so-called "counter steering";
I can't find ...
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Why does pitch in a helicopter take effect 90 degrees later?
In a helicopter if you want to give it a forward pitch, you change the angle of the blades when it is in this position ----
So the two blades experience unequal lift and because o gyroscopic ...
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MEMS gyroscope and orientation
I'm trying to understand how a MEMS gyroscope can give you orientation. The question may not make any sense, I may have some misunderstandings about the different topics...
From the Wikipedia page ...
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Will a wheel rolling down a hill ever fall over?
Say I have a detached bicycle wheel and I roll it down an infinite, flat, asphalt inclined plane, in air (ie there will be a terminal velocity). When, if ever, will the wheel fall over?
I've been ...
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What happens when I roll a gyroscope along its axis of spin?
Say:
I have a gyroscope that is spinning in the xy plane along the z axis.
I then roll its spinning axis by some angle theta
Now I know the gyroscope will resist my attempting to change its axis of ...
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How, exactly, does a reaction wheel work?
Reaction wheels, mounted on spacecrafts and satellites, are used for precision attitude control. It is not clear to me how they can do this, though.
My best guess is that when a motor accelerates a ...
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Measuring Earth rotation rate about its axis with gyroscopes
With gyroscopes having two basic properties, precession and rigidity in space, shouldn't we see an apparent movement (due to rigidity in space) of a gyroscope's rotor (gimbals) in relation to the ...
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Gyroscope in an airplane following the curve of the Earth
This video from a high-profile skepticism channel perports to debunk a flat-Earth nut. But, Greg’s explaination of why the artificial horizon instrument on an aircraft works properly seems to me to be ...
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What gives energy for precessional motion of gyroscope?
Let us suppose we have an ideal friction-less gyroscope and it is suddenly given an angular momentum, and left as in the figure. It will start precessional motion.
Since there is no friction, the ...
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What causes precession or nutation in a spinning object?
What causes precession in a spinning object?
What causes nutation in a spinning object?
What causes a top, gyroscope, and the earth to wobble?
Just because it's a simple question, I'm not expecting ...
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Mech stability through gyroscope
I recently read up about gyroscopes, angular momentum and mechs (the big Cockpit controlled robots) and was wondering if it would be possible to get a stable walking mech (only as example, not meant ...
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Dual gyro system: will it resist a turning force?
Let's say there are 2 gyroscopes. Both are connected to the same frame (orange). Both are spinning at the same speed, but in opposite directions (red).
If I spin the frame (green arrow), the gyros ...
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The moment of inertia of a spinning gyroscope assembly
Moment of Inertia (MOI) is typically used to describe a rigid body, so I don't know how well I can express my question in those terms. However, it seems like the best framework for getting at my issue....
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Gyroscope's motion explained by internal forces
I'm having a hard time trying to figure out the inner mechanisms behind a gyroscope's precession and nutation. To be very specific, I want to consider gyroscopes like this one:
(source: wordpress.com)...
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Minimum speed needed for a gyroscope to precess
I was reading about gyroscopes and their precession. Based on the text, the angular speed of precession is: $\omega_{precession}=\dfrac{\tau}{L}$ But intuitively, if the wheel of the gyroscope is ...
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SLR camera gyroscopic stabilization - limited by rotation of the earth?
In this photography stackexchange answer it is stated that the limits of performance of gyroscopic stabilization of an Olympus handheld camera is related to the rotation of the earth. I'm further ...
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What does a MEMS gyro measure during off-axis rotations?
I've been working with MEMS gyroscopes in hobbyist projects for years—but it's recently come to my attention that I don't have any principled understanding of what rotation rate measurements ...
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Why do gyroscopes not maintain their stability as seen in this video?
What exactly causes gyroscopes to oscillate as seen in this video.
http://www.youtube.com/watch?v=gdAmEEAiJWo
Even when my toy gyroscope spins on Earth, I get oscillations. Is this a result of ...
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New way to compensate for gyroscopic drift
Let us assume two points in 3D space and we only care about their orientation, no velocity, position or acceleration.
Now connect those two points with a rigid body of certain length, so that the ...
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Gyroscopic Force/Torque of a Constrained Wheel
Description
I have a wheel spinning away from me in the vertical plane. The angular momentum is pointing to the left. The axis of rotation is horizontal, and it is supported on either side by a ...
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Understanding gyroscopes
Considering the typical situation of a rotating bicycle wheel held by one end of its axle by a rope tied to the ceiling: gravity torque is the time derivative of the angular momentum, and in this case ...
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What will be the radius of the circle of the rolling coin? Gyroscope task [closed]
I try to calculate the radius of the rolling coin. The task was found in physics book https://www.amazon.co.uk/General-Course-Physics-1-Mechanics/dp/5922102257 (only in Russian). But unfortunately my ...
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An expert opinion on controversial video appearing to defy Newton's Laws [closed]
I really want another answer to this question than just my own.
As many people probably know the late Prof Laithwaite in the UK (a brilliant electrical engineer) made the error of wandering outside ...
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Lagrangian of the Euler equations - why are Lin constraints required?
The following equation describes the motion of a rigid body rotation, such as a gyroscope:
$$
\frac{d\textbf{L}}{dt} ={\bf{\tau}}= \textbf{r}\times m\textbf{g}= {\omega}\times \textbf{L}$$
where $...
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Dynamics of pendulum coupled to a gyroscope [closed]
We know the dynamics of a pendulum and we know the dynamics of a gyroscope. I put together the following I diagram below. The interesting thing as that the system has a beat frequency where the ...
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Will a precessing spinning wheel fall down if there is no friction at all?
If there where no friction at all, would a spinning wheel held up by one end of the axis spin precess forever without falling down?
I just asked another question about the same problem:
Direction ...
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Anti-gravity wheel?
So I was just watching some YouTube videos on a spinning wheel that seemed to "defy" gravity. The creator made two videos on it, the first showing the wheel, and the second with an attempt ...
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Direction of torque precession of a spinning wheel
Consider a spinning wheel, which is held up by one end of it's axis like this:
To explain why the change of angular momentum is directed as shown in the figure above, one usually says that there is ...
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Is the torque on a gyroscope a conventional virtual force perpendicular to rotation?
So I am having some difficulty understanding gyroscopic precession. I understand that mathematically by convention torque is perpendicular to the force and so is angular momentum but surely that force ...
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How does a gyrocompass in a moving craft sense the Earth's rotation?
Various descriptions of gyrocompasses that I can find (such as the Wikipedia article) claim that the compass will seek to align itself with the earth's rotational axis.
I think I can understand how ...
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Are gyroscopes the only way to maintain the orientation?
Gyroscope is quite popular, one can even find it in iphone etc. But, is such
Gyroscope the only way? are there any other ways to build machine that to measure or maintain the orientation?
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Flat Earth experiment, but with gyroscope
A man conducted "an experiment" (quotes really, really necessary) to prove that earth is flat. Here's a link. He used a spirit level, set it up before takeoff and expected the level to be tilted after ...
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